Dipper front



A. H. EXTON DIPPER FRONT Filed Jan. 5, 1929 2 Sheets-Sheet 1 March 31, 1931. A. H. EXTON 1,793,373

' DIPPER FRONT Filed Jan. 5, 1929 2 Sheets-Sheet 2 Patented Mar. 31, 1931 UNITED STATES PATENT OFFICE ALFRED H. EXTON, OF CHICAGO HEIGHTS, ILLINOIS, ASSIGNOR TO AMERICAN MAN- GANESE STEEL COMPANY, OF CHICAGO HEIGHTS, ILLINOIS, A CORPORATION OF MAINE DIPPER FRONT Application filed January 5, 1929. Serial No. 330,513.

This invention relates to improvements in the construction of dipper fronts and dipper teeth adapted to be secured to the lip of the dipper front.

Excavating buckets commonly have dipper fronts having a forward cutting edge and digging lip to which a plurality of digging teeth are secured by detachable base members. Dipper teeth are so designed that either the tip of a two-part tooth or an integral tooth and base may be easily detached or removed when worn out. The connections between the tips and bases and between the bases and the dipper lip must be capable of withstanding the heavy stresses incurred while the dipper is in use. The inside of the dipper front is desired to be substantially smooth and free from projections in order that the material may be fully discharged.

One purpose of my invention is to design the front of the dipper so that the digging lip is plane with the rearward part of the front. the seats for the digging teeth being inclined forming recesses for the inner shanks of the dipper teeth. Thus the dipper operates equally well in rock or clay since sticky material does not lodge and stick on the forward edge of the front which may occur if the entire front is flared or inclined.

Another object of my invention is to so design the digging teeth that the main body of the secured base of the tooth is on the outside of the front and the shorter inner shank rests in a depression on the inner side of the front thereby offering the least amount of resistance to the material in digging and discharging and placing the greatest amount of metal on the outside where the largest amount of wear occurs.

A further object of my invention is the provision of locking means in addition-to the ordinary securing bolts between the tooth and the digging lip comprising a lug on the tooth entering into an open socket formed at the end of a recess on the inner side of the dipper front.

Other and additional objects will be apparent from a full and detailed description of my invention.

In the drawings wherein I have shown one embodiment of my invention Figure 1 is a bottom View of a dipper front having three of the four digging teeth secured to the forward edge.

Figure 2 is a vertical section on line 2-2 of Figure 1.

Figure 3 is a forward view of the dipper front shown in Figure 1.

Figure 4 is a plan view of a portion of a dipper front having a tooth secured thereto and showing the locking means.

Figure 5 is a vertical elevation of Figure 4 showing the digging lip in section on line 55 of Figure 4.

Figure 6 is a perspective view of my improved dipper tooth.

A dipper front designated 1 is of usual design having a thickened rearward heel 2 and side members 3 for attachment to the bucket and having a forward lip 4. It will be noted that the lip 4 is plane with the rearward portion of the dipper front except for the recesses in which the dipper teeth 5 are secured. The dipper teeth 5 are formed with a short inner shank 6 and a longer outer attaching shank 7. Securing means 8 and 9 hold the rearward end of the outer shank 7 to the digging lip while the securing means 10 extends through both shanks 6 and 7 and digging lip 4. The attaching portions of the digging lip 4 are formed by recesses 11 cut in the inner side of the dipper front inclined downwardly and outwardly towards the. edge of thelip. On the outside of the front, inclined projections 12 corresponding to the incline of the recesses 11 are formed. Thus the shank 6 of the tooth is secured in recess lland the shank 7 of the tooth is secured to the outer projection 12. In addition to the securing bolts 8, 9 and 10, the tooth 5 is designed with an addi tional locking lug 13 formed at the lower edge of the inner shank 6 and extending rearwardly. This lug 13 extends beneath a raised lip or bridge 14. The raised lip 14 is formed at the end of the recess 11 by openings '15 and 16 extending at angles to each other, thus forming a continuous opening beneath the lip 14. Thus, in Figure 5, the lug 13 is shown extending partially into opening 15 beneath the lip 14 whereby the end of the tooth is securely held.

In order to strengthen the construction of the front wall and to provide suflicient metal for the seat portions of the dipper teeth bases, it will be noted in Figure 2 that the front Wall has a gradually increasing thickness from a'point slightly beyond the inner end of the outer shank 7 and towards the edge of the front. The portions of the front walls between the teeth are slightly beveled at the outer edges to form cutting lips which lie substantially in the main plane of the front wall. The portions of the front wall which serve as seats-for the dipper teeth bases are depressed and outwardly inclined relative to the plane of the front wall. It will be apparent that the thickness of the front wall in a plane across the width thereofwill be sub stantially uniform and a strong and reinforced construction is provided without the necessityof materially thickening the front wall to form seat portions. for the dipper teeth. In former constructions the seat portions for the teeth have either been formed by relatively thick strengthened ribs usually on the interior of the front wall thereby forming material obstructions to the passage of material into the .dipper or by forming projections from the front wall which receive therebetween the shanks of the dipper teeth.

It will be particularly noted that due to the provision of a longer outer attaching .shank the greatest amount of metal is placed on the side where the greatest amount of wear occurs, that is, on the outside of the bucket, thus the tooth'base has a longer life.

1 14 allows uniform heat treatment and is an improvement over prior constructions in which the lug on the'tooth base was received in a recess closed except for the entrance opening.

I have described one embodiment of my invention but other modifications coming within the scope of my appended claims will be readily apparent.

I claim 1. A dipperfront having spaced depressions on the inside face extending inward from the lip, said depressions being inclined downwardly towards the edge of the lip, raised portions on the outside of the dipper front corresponding to the inside depressions, said front having a raised lip at the end of each of the depressions and a continuous opening extending beneath the raised lip.

side of the lip opposite said depressions, saidraised portions being inclined parallel to said depressions, said depressions and raised portions forming attachment bases for dipper teeth.

. 4. A dipper front comprising a digging lip having'inclined recesses spaced along the inner side and forming tooth seats, the remainder of said lip being plane with the rearward portion of the dipper front, raised portions on the outside of the dipper lip, dipper teeth having short inside shanks seated in said recesses, said teeth having longer outer shanks secured to said raised portions of the dipper lip. 7

5. A dipper front comprising a front wall formed at its upper and'outer end with a gradually increasing thickness towards cutting edges substantially in the main plane of the front wall, said front wall having dipper tooth seats outwardly inclined relative to the plane of the front wall whereby the interior of the front is substantially smooth and free from obstructions.

6. A dipper front comprising a front wall formed at its upper and outer end with a gradually increasing thickness towards its edge, said front wall having alternate portions of its edge depressed and outwardly inclined to form seats for dipper teeth, the portions between said seats forming cutting edges substantially in the main plane of the front wall.

7. A dipper front comprising a front wall formed at its upper and outer end with a gradually increasing thickness towards its edge, said front wall having alternate portions of its edge depressed and outwardly inclined to form seats for dipper teeth, the portions between said seats forming cutting edges substantially in the plane of the front wall'and dipper teeth having bifurcated attaching portions forming short inner legs adapted to fit into the depressions of said front wall and longer outer shanks adapted to be secured against the exterior of the front wall whereby the interior of the dipper front is substantially smooth and free from obstructions with the dipper teeth in place.

Signed'at Chicago Heights, Illinois, this 31st day of December. 1928.

ALFRED H. EXTON. 

